zsh in screen - bad erase key ^@ instead of ^H or ^?

zsh in screen - bad erase key ^@ instead of ^H or ^?

[Chuck]

How do I tell zsh in screen that my backspace key is ^H or ^? instead of
^@ as it currently thinks? stty erase '^@' fails as does using tset.
^v(bs key) tells me bs is currently ^@. zsh works great outside of
screen just not quite right inside it. Version is 4.3.2 gentoo stable build.
Any pointers would be greatly appreciated.
Thanks!

Re: zsh in screen - bad erase key ^@ instead of ^H or ^?

[Peter Stephenson]

On Mon, 17 Dec 2007 23:09:55 -0800
Chuck <GBSCDcM8oX5F7qrd@spambox.us> wrote:
> How do I tell zsh in screen that my backspace key is ^H or ^? instead of
> ^@ as it currently thinks? stty erase '^@' fails as does using tset.

It may be you're doing the opposite of what you need...

> ^v(bs key) tells me bs is currently ^@.

...this indicates the backspace key currently *is* sending ^@, because
the ^V stops zsh interpreting the character.

So instead, try making it so that it sends ^H or ^?: "stty erase '^?'".
(This is likely to be some artefact of screen since zsh doesn't
change special characters of that sort.)

If for some reason you're stuck with the backspace key sending ^@, you
can use "bindkey" to tell zsh to use it for functions usually bound with ^?
and ^h, but you shouldn't need to do that.

-- 
Peter Stephenson <pws@csr.com>                  Software Engineer
CSR PLC, Churchill House, Cambridge Business Park, Cowley Road
Cambridge, CB4 0WZ, UK                          Tel: +44 (0)1223 692070

Re: zsh in screen - bad erase key ^@ instead of ^H or ^?

[Wayne Davison]

On Mon, Dec 17, 2007 at 11:09:55PM -0800, Chuck wrote:
> ^v(bs key) tells me bs is currently ^@.

Check your screenrc files to see if the backspace key is being handled
specially.  I've seen the following in /etc/screenrc on some older systems:

bindkey -d -k kb stuff ^H

Perhaps yours has ^@?  You can override this by leaving off the "stuff"
command:

bindkey -d -k kb

..wayne..

Re: zsh in screen - bad erase key ^@ instead of ^H or ^?

[Chuck]

Peter Stephenson wrote:
> On Mon, 17 Dec 2007 23:09:55 -0800
> Chuck <GBSCDcM8oX5F7qrd@spambox.us> wrote:
>   
>> How do I tell zsh in screen that my backspace key is ^H or ^? instead of
>> ^@ as it currently thinks? stty erase '^@' fails as does using tset.
>>     
>
> It may be you're doing the opposite of what you need...
>
>   
>> ^v(bs key) tells me bs is currently ^@.
>>     
>
> ...this indicates the backspace key currently *is* sending ^@, because
> the ^V stops zsh interpreting the character.
>
> So instead, try making it so that it sends ^H or ^?: "stty erase '^?'".
> (This is likely to be some artefact of screen since zsh doesn't
> change special characters of that sort.)
>   
Unfortunately, bs really is sending ^@ in screen and I cannot change it.
stty erase '^H' or '^?' doesn't change bs at all. It's as if the key
mapping at a lower level is screwed up.
> If for some reason you're stuck with the backspace key sending ^@, you
> can use "bindkey" to tell zsh to use it for functions usually bound with ^?
> and ^h, but you shouldn't need to do that.
>   
I added a bindkey "^@" "backward-delete-char" in my zshrc when TERM =
screen and I can hit bs and it works in zsh proper. If I run vim though,
my editor of choice, the bs key just throws me out of edit mode instead
of deleting the previous char.

Re: zsh in screen - bad erase key ^@ instead of ^H or ^?

[Chuck (vid,smtp3)]

Nope, no bindkeys like that. I tried to force

bindkey -d -k kb stuff ^H

but it didn't have any affect.

Wayne Davison wrote:
> On Mon, Dec 17, 2007 at 11:09:55PM -0800, Chuck wrote:
>   
>> ^v(bs key) tells me bs is currently ^@.
>>     
>
> Check your screenrc files to see if the backspace key is being handled
> specially.  I've seen the following in /etc/screenrc on some older systems:
>
> bindkey -d -k kb stuff ^H
>
> Perhaps yours has ^@?  You can override this by leaving off the "stuff"
> command:
>
> bindkey -d -k kb
>
> ..wayne..
>
>   

Re: zsh in screen - bad erase key ^@ instead of ^H or ^?

[Peter Stephenson]

Chuck wrote:
> Unfortunately, bs really is sending ^@ in screen and I cannot change it.

If that's the case, then bindkey in zsh is your only hope.

> stty erase '^H' or '^?' doesn't change bs at all. It's as if the key
> mapping at a lower level is screwed up.

zsh does have the capability to freeze the terminal settings:  make sure
you have "ttyctl -u" in effect.  "ttyctl" on its own will tell you what
the current state is.  If it reports "tty is not frozen" I think you've
run out of things you can do in the shell.

-- 
Peter Stephenson <pws@csr.com>                  Software Engineer
CSR PLC, Churchill House, Cambridge Business Park, Cowley Road
Cambridge, CB4 0WZ, UK                          Tel: +44 (0)1223 692070

Re: zsh in screen - bad erase key ^@ instead of ^H or ^?

[Chuck (vid,smtp3)]

Peter Stephenson wrote:
> Chuck wrote:
>   
>> Unfortunately, bs really is sending ^@ in screen and I cannot change it.
>>     
>
> If that's the case, then bindkey in zsh is your only hope.
>
>   
>> stty erase '^H' or '^?' doesn't change bs at all. It's as if the key
>> mapping at a lower level is screwed up.
>>     
>
> zsh does have the capability to freeze the terminal settings:  make sure
> you have "ttyctl -u" in effect.  "ttyctl" on its own will tell you what
> the current state is.  If it reports "tty is not frozen" I think you've
> run out of things you can do in the shell.
>   
It reports that the tty is not frozen. :(

Re: zsh in screen - bad erase key ^@ instead of ^H or ^?

[Chuck]

Ok, I just did a ^K BS and it output <Nul> instead of <BS>. I can get
around this in vim by mapping <Nul> to <BS> but there's problems sshing
or using any program that uses bs. Anyone know how to change my
backspace key codes? I'm pretty sure that's the problem.  stty erase
blah doesnt seem to work, and I cant force a ttyctl f before running the
screen...
Thanks!



Peter Stephenson wrote:
> Chuck wrote:
>   
>> Unfortunately, bs really is sending ^@ in screen and I cannot change it.
>>     
>
> If that's the case, then bindkey in zsh is your only hope.
>
>   
>> stty erase '^H' or '^?' doesn't change bs at all. It's as if the key
>> mapping at a lower level is screwed up.
>>     
>
> zsh does have the capability to freeze the terminal settings:  make sure
> you have "ttyctl -u" in effect.  "ttyctl" on its own will tell you what
> the current state is.  If it reports "tty is not frozen" I think you've
> run out of things you can do in the shell.
>
>   

Re: zsh in screen - bad erase key ^@ instead of ^H or ^?

[Vincent Lefevre]

On 2007-12-18 12:26:47 -0800, Chuck wrote:
> Ok, I just did a ^K BS and it output <Nul> instead of <BS>. I can get
> around this in vim by mapping <Nul> to <BS> but there's problems sshing
> or using any program that uses bs. Anyone know how to change my
> backspace key codes? I'm pretty sure that's the problem.  stty erase
> blah doesnt seem to work, and I cant force a ttyctl f before running the
> screen...

You have a problem with your "screen" utility. FYI, a search for

  screen backspace nul

on Google gives:

  https://bugs.launchpad.net/ubuntu/+source/screen/+bug/29787

-- 
Vincent Lefèvre <vincent@vinc17.org> - Web: <http://www.vinc17.org/>
100% accessible validated (X)HTML - Blog: <http://www.vinc17.org/blog/>
Work: CR INRIA - computer arithmetic / Arenaire project (LIP, ENS-Lyon)

Re: zsh in screen - bad erase key ^@ instead of ^H or ^?

[Chuck]

Awesome!! That was my problem! Thanks so much
 -Chuck

Vincent Lefevre wrote:
> On 2007-12-18 12:26:47 -0800, Chuck wrote:
>   
>> Ok, I just did a ^K BS and it output <Nul> instead of <BS>. I can get
>> around this in vim by mapping <Nul> to <BS> but there's problems sshing
>> or using any program that uses bs. Anyone know how to change my
>> backspace key codes? I'm pretty sure that's the problem.  stty erase
>> blah doesnt seem to work, and I cant force a ttyctl f before running the
>> screen...
>>     
>
> You have a problem with your "screen" utility. FYI, a search for
>
>   screen backspace nul
>
> on Google gives:
>
>   https://bugs.launchpad.net/ubuntu/+source/screen/+bug/29787
>
>